Sewing-machine feed mechanism.



PATENTED FEB. 28, 1905. J. BIGELOW.

SEWING MACHINE FEED MECHANISM.

APPLICATION FILED JAN. 2, 1904.

Al/r/vzmrza NITED STATES Patented February 28, 1905.

JOHN BIGELOWV, OF MINNEAPOLIS, MINNESOTA.

SEWING-MACHINE FEED MECHANISM.

SPECIFICATION forming part of Letters .tatent N0. 783,412, datedFebruary 28, 1905. Application filed January 2, 1904. Serial No.187,495.

To a whom it may concern:

Be it known that I, JOHN BIGELOW, of Minneapolis, in the county ofHennepin, State of Minnesota, have invented certain new and usefulImprovements in Sewing-\llachine Feed Mechanism, of which the followingis a speciiication.

This invention relates to improvements in feed mechanisms forsewing-machines, and particularly to feed mechanisms for the class ofsewing-machines known as single-thread loop-stitch machines, of whichthe Willcox & Gibbs Automatic is an illustration. In an application forLetters Patent filed by me September 26, 1903, Serial No. 174,702, Ihave described and claimed the modified form of looper which I use,while in my present application I describe and claim my reversible feedmechanism.

The object of this mechanism is to feed the work either forward orbackward or to hold it relatively stationary while a number of stitchesare taken to knot or tie the end of the seam.

A further object of the invention is to provide a simple mechanism foradjusting and indicating the length of the stitches.

A still further object of the invention is to automatically lock thereversible stitch mechanism each time it is set for forward and backwardstitching.

To these ends the invention consists, generally, in the constructionsand combinations hereinafter described,and particularly pointed out inthe claims. i

In the accompanying drawings, forming part of this specification, Figure1 is a side elevation and partial section of a sewing-machine embodyingmy reversible stitch mechanism, which is here shown as set to take aforward stitch. Fig. 2 is a plan View of the lower part of the machine,a portion of the work-plate being broken away to show the mechanismarrangedbeneath the same. Fig. ,3 is a detail section on line a; w ofFig. 1 looking in the direction of the arrow. Fig. 4 is a detail sideelevation showing the parts adjusted for making a backward stitch. Fig.5 is a detail of the cam-piece by which the length of the stitch isadjusted.

In the drawings, 1 represents the needle and needle-bar; 2, thepresser-foot; 3, the work-plate; 14, the frame of the machine; 4, thefeed-dog; 5, the feed-dog carriage; 6, the feed-dog-carriage rod; 7 thedriving-shaft of the machine, and 8 a rocking lever pivoted to the frameof the machine by the screw or stud 9 and provided at one end with ayoke 10, embracing an eccentric arranged on the drivingshaft 7. Theother end of this rocking lever is connected by a pin or screw 11 to alink 12, the opposite end of said link being pivotally connected by ascrew or pin 13 with the feeddog-carriage rod 6, which latter isconnected by the pin 15 with the feed-dog carriage 5. By this connectionthe rocking lever 8 receives a vibratory motion through the yoke 10 fromthe eccentric on the driving-shaft'T. (See Fig. 1.) This vibratorymotion is transmitted through the lever 8 and the link 12 to the end ofthe feed-dog-carriage rod 6. The feed-dogcarriage rod 6 is provided witha stud carrying a roller 37 (see Fig. 3,) and this roller engages anopen-faced cam 18. By this means I change the vertical movement receivedthrough the link 12 and lever 8 from the eccentric on shaft 7 to ahorizontal reciprocating or forward-and-back motion that is transmittedto the feed-dog carriage 5 and feed-dog 4. By making the angle of theopen-faced cam 18 adjustable the stitch is made longer or shorter, or bybringing the cam to a vertical positionthe feed-dog will bestationary-that is, it will have no forward or backward movement.

The part represented at 19 is the feed-indicator and adjustment-piece.It is provided with a hollow shaft (see Fig. 3) which projects throughthe frame 14 of the machine and is secured, preferably, by aspring-washer 20 and a nut 21. Sufficient tension is placed on thewasher 20 to enable the piece 19 to be freely swung on its center byitshandle 19, while at the same time the adjustment-piece 19 will remain inany position in which it is set. On its upper edge the piece 19 has abroad face 22, (see Fig. 2,) marked on its upper side with numeralsindicating the length of stitch at which it is set, which numerals showthrough a slot in the work-plate 3, (see Fig. 1,) as in the presentwell-known Willcox & Gibbs Automatic machines.

Beneath its broad face 22 the adjustmentpiece 19 has a long slot 23,removed from its center of rotation at one end and approaching it at theother. This cam-slot 23 engages a pin 24 on the end of one arm of arocking lever 25, pivoted at 25 to the frame of the machine, the otherend 26 of'said rocking lever being free. It follows then that when thehandle of the adjustment-piece 19 is at its lowest point, as shown inthe drawings, and the indicator shows twelve stitches to the inch theend 24 of the rocking lever 25 will be raised to its farthest point fromthe center, on which the piece 19 turns, and the point 26 of saidrockinglever will be depressed. Swinging the handle 19 to its extreme inthe opposite direction will cause the indicator to show thirty stitchesto the inch, and the point 24 of the lever will be brought nearer thecenter of said adjustment-piece and the point 26 will be raised. Theengagement of the pin or end 24 of the rocking lever 25 in the slot inthe adjustment-piece 19 limits the extent of movement of saidadjustment-piece. The openfaced cam 18 has a shaft 27 projectingcentrally from its opposite or back side, which shaft fits into thehollow shaft, before referred to, of the feed-adjustment piece 19. Onone side of its face said cam has an upwardly-projecting arm 28, towhich one end of the link 30 is pivotally connected by the screw 29. Theother end of said link 30 is pivotally connected by a pin or screw 31 toa disk 32 on the end of a rod 32, having a bearing 33, secured to theframe 14. The other end of the rod is provided with a head 34, which islocated at one side and just beyond the edge of the workplate 3 forconvenience in handling. On its upper side the link 30 has adouble-inclined plane which is pressed upon by a spring 35, secured inthe frame 14. The lower end of the link 30 rests on the end 26 of thefeed-adjustment lever 25, which forms an adjustable stop for said linkand controls the amount of its throw, for when the point 26 of the leveris depressed through the head 34 the link 30 can be given a greaterthrow than when the point 26 is raised. open-faced cam-piece 18 at agreater or less angle and the movement conveyedback to the feed-dog beincreased or decreased. The pressure of the spring 35 on the risingincline of the link 30 forces its lower side against the point of theadjustment-lever at 26 and se curely locks said link in such position,and through the link connection with the openfaced cam 18 it necessarilyholds said cam firmly at any desired angle, and the vertical movement ofthe end 13 of the feed-dog rod, through the roller connection with. saidcam, is converted to a horizontal movement at its opposite end, which isconveyed through the feed-dog carriage to the feed-dog. The posi- Thusthe link can set the tion of the parts described for making a forwardstitch is shown in Fig. 1 and for making a backward stitch in Fig. 4. Bybringing the spring 35 to the top of the double incline on the link 30,which the operator can easily determine by the tension on the head 34,the slot in the open-faced cam 18 will be in a vertical position and nomovement of the feed-dog will follow except an up-and-down movementreceived from the eccentric on the driving-shaft of the machine on whichthe free end of said carriage rests. The spring 17 in the feed-dogcarriage 5 by pressing at one end on said carriage and at its other onthe pin 16 serves to prevent a rattling noise from lost motion onaccount of looseness in any of the driving parts. This spring may bemade very light, as it is not required to give the backward movement tothe feed-dog and its carriage, as in the well-known Willcox & GibbsAutomatic machine, both the forward and backward move ments inmy machinebeing occasioned by the positive engagement of both arms of the yoke 10with both sides of the eccentric on the driving-shaft instead ofengagement with one side only, as in the said Willcox & Gibbs machine.-

The looper 36 (see Fig. 2) I have described and claimed in my saidpending application.

It is shaped to carry one side of the loop which 9 it is holding to theside and back of the needle when making a backward stitch, so that itshook will take a new loop from the needle and pass it through the oldone held by the hook to make a stitch.

The operation of the parts described is as follows: Move the handle 19until the figure on the indicator 22 shows through the opening in thework-plate the length of stitch desired. The spring-pressure on the topof the link 30 allows this link to yield to the movements of the point26 of the adjustment-lever and to automatically adjust itself to agreater or less length of stitch. By turning the head 34 forward for aforward stitch and backward for a backward stitch the link 30 is movedforward or backward, and through its connection 29 with the open-facedcam 18 it sets said cam at the-desired angle to make the stitchrequired, while the pressure of the spring 35 on the reverse side of theinclined plane on the top of said link 30 holds the bottom side of saidlink against the point 26 of the adj ustmentlever 25 and securely lockssaid parts. Then by the revolution of the driving-shaft the eccentricthereon, through the rocking lever 8 and link 12, gives a verticalvibration equally above and below the center of the open-faced cam 18 tothe feed-dog rod 6, which, aspreviously stated, engages said cam througha suitable stud arranged upon said rod and carrying a roller 37. Theangle at which the cam 18 is set changes the vertical movement of therod 6 at one end to a forward-and-backward movement at the other end,where said rod is pivotally connected to the feed-dog carriage. Theforward-and-backward movement is assisted by the fact that above thepivotal point 15 the said carriage is supported by a stud 16, on whichit is free to move only forward and backward. The free end of thefeed-dog carriage 5 rests on the eccentric on the driving-shaft of themachine, by which the feed-dog it carries is raised above the workplateto move the work. The forward or backward movement of the dog then takesplace, thus carrying the work beneath the presserfoot with it. Theeccentric recedes and the feed-dog carriage follows it, owing to theaction of the spring 17 pressing on the stud 16 and the connection ofthe rod 6 at 15 below the center on which the carriage swings. When thefeed-dog has thus receded below the work-plate, it moves into positionto again engage the work. The feed-dog receives all of its movements, upand down, back and forward, from a single eccentric on the drivingshaftof the machine and operates in the feeddog slot in the work-plate of thepresent machine without a'ny change when the openfaced cam 18 is pivotedon its center and the vertical movement of the end of the rod 6 isequally above and below said center.

The adjustable stop formed by the end of the lever 25, together with thelink connected to the cam 18, forms an independently operable andadjustable limiting device for said cam. This limiting device isconnected to and adjusted by the stitch-indicator, and it forms a meansof regulating the stroke of the feed-dog, and consequently the length ofthe stitches, whether the machine is sewing forward or backward.

1 claim as my invention .1. 1nasewing-machinehavingits feed mechanismactuated by a single eccentric on the driving-shaft, the combination,with a feeddog carriage and feed-dog, of a reversible feedcontrollingcam, a gage, a stitch-indicator provided with a cam for adjusting saidgage, and mechanism for changing the angle of said feedcontrolling camand automatically holding the same with spring-pressure in any desiredposition determined by said indicator and gage to make interchangeablyforward or backward stitches of equal length, substantially asdescribed.

2. In a sewing-machine, the combination, with a feed-dog and feed-dogcarriage, of a single eccentric on the driving-shaft of the machine foractuating all of the movements of' said feed-dog, means connecting saideccentric and said feed-dog carriage with a reversible cam forcontrolling the forward and backward movements of said feed-dog, anadjustable gage-point, and means held in yielding contact against saidgage-point by spring-pressure, by which the angle of said cam can bechanged for making either a forward or backward feed action of equallength without changing the position of said gage-point.

3. In a sewing-machine, the combination with a feed-dog and feed-dogcarriage, of a reversible feed-controlling cam, and means connectingsaid carriage with said cam, a handcontrolled disk, a link pivoted atone end to said cam and at its other end to said disk and having twodepressions on its upper edge with a swell between them, an adjustablegage, and a spring acting upon the upper edge of said link and causingsaid link as soon as its pivoted bearings have passed over theircenters, either way, to descend against and be held by said adjustablegage-point, as and for the purpose set forth.

4. In a sewing-machine, the combination, with a feed-dog, of afeed-controlling cam, means connecting said feed-dog with said cam, alink having one of its ends pivotally con nected with said cam, arotatable disk under the control of the operator to which the other endof the link is connected, said link having its upper edge formed withtwo depressions and an intermediate flat elevation or double inclinedplane, a spring pressing upon the inclined. surface of said link andarranged to be directly over the angle of said inclined planes when thecam is in a vertical position, and an adjustable stop against which saidlink is pressed by said spring, substantially as described.

5. In asewing-machine havingits feed mechanism actuated by a singleeccentric on the driving-shaft, the combination, with the feeddog andfeed-dog carriage, of a reversible feed-controlling cam, meansconnecting said eccentric and said feed-dog carriage with said cam, astitch-indicator, a single gage-point receiving adjustment from saidindicator, which limits the means for adjusting the angle of thefeed-cam to any desired length of stitch, but leaves said means free tochange the feed action to either a forward or backward direction,substantially as described.

6. In a sewing-machine, the combination with a feed-dog, of anoscillatory feed-controlling cam, means for connecting said feed-dog andsaid cam, an independent oscillatory hearing, a link connecting saidbearing with said cam for controlling its movements, a spring arrangedto apply pressure on said link, and limiting devices for said cam todetermine the amount and direction of motion conveyed to said feed-dogfrom the cam and thereby the direction and length of stitch,substantially as described.

7 In a sewing-machine, the combination, with the pivoted reciprocatingfeed-dog carriage 5 and feed-dog 4 carried thereby, of the driving-shaftprovided with an eccentric 7, on which one end of the feed-dog carriagerests and by which it is raised and lowered, the

rocking lever 8 engaging said eccentric, the

rod 6 pivoted to said carriage, the link 12 connecting the lever 8 andthe rod 6, the openfaced reversible cam 18 and the roll 37 engaging saidcam, substantially as described.

8. In a sewing-machine, the combination, with the feed-dog carriage,feed-dog and operating-rod 6, of the feed-controlling cam 18, the link30 pivotally connected at one end to said cam and at its other end torotatable means for operating said link, the adjustable stitch-indicator19 provided With a cam-slot 23 and the pivoted lever engaging said slotand having an adjustable point forming a stop for said link,substantially as described.

9. In a sewing-machine, the combination, With the pivoted reciprocatingcarriage, the feed-dog 4; arranged thereon and the operating-rod 6pivotally connected to said carriage, of the driving-shaft provided Withthe eccentric 7 upon which the free end of said carriage is supported,the rocking lever 8 provided with a yoke 10 engaging saideccentric, thelink 12 connecting the lever 8 and the rod 6, the reversiblefeed-controlling cam 18, the roll 37 secured to the end of the rod 6 andengaging said cam, and means for reversing the position of said cam,substantially as described.

In Witness whereof I have hereunto set my hand this 24th day ofDecember, 1903.

JOHN BIGELOW. In presence of A. (J. PAUL, (J. G. HANSON.

